Taking pictures of eyes


Addicted to pilates geek
Has anybody got any tips for taking pictures in close-up of eyes to show work done? The pictures themselves are okay because I've learned about the macro setting but I would like any ideas about lighting to prevent shadows and most importantly about setting the subject.

I've seen lots of great close-ups of eyes on this site, but how do you ensure that the model doesn't look boss-eyed or google-eyed in the picture? It seems I am capable of making even the most normal looking model seem totally weird in a picture.